
#include "Camera.h"

Camera::Camera(glm::vec3 position, glm::vec3 up , float yaw, float pitch)
	: Front(glm::vec3(0.0f, 0.0f, -1.0f)), MovementSpeed(SPEED), MouseSensitivity(SENSITIVTY), Zoom(ZOOM) {
	Position = position;
	WorldUp = up;
	Yaw = yaw;
	Pitch = pitch;

	UpdateCameraVectors();
}

// Constructor with scalar values
Camera::Camera(float posX, float posY, float posZ, float upX, float upY, float upZ, float yaw, float pitch)
	: Front(glm::vec3(0.0f, 0.0f, -1.0f)), MovementSpeed(SPEED), MouseSensitivity(SENSITIVTY), Zoom(ZOOM) {
	Position = glm::vec3(posX, posY, posZ);
	WorldUp = glm::vec3(upX, upY, upZ);
	Yaw = yaw;
	Pitch = pitch;

	UpdateCameraVectors();
}

glm::mat4 Camera::GetViewMatrix() {
	return glm::lookAt(Position, Position + Front, Up);
}

void Camera::ProcessKeyboard(Camera_Movement direction, float deltaTime) {
	float velocity = MovementSpeed * deltaTime;
	if (direction == FORWARD)
		Position += Front * velocity;
	if (direction == BACKWARD)
		Position -= Front * velocity;
	if (direction == LEFT)
		Position -= Right * velocity;
	if (direction == RIGHT)
		Position += Right * velocity;
}

void Camera::ProcessMouseMovement(float xoffset, float yoffset, GLboolean constrainPitch) {
	xoffset *= MouseSensitivity;
	yoffset *= MouseSensitivity;

	Yaw += xoffset;
	Pitch += yoffset;

	// Make sure that when pitch is out of bounds, screen doesn't get flipped
	if (constrainPitch) {
		if (Pitch > 89.0f)
			Pitch = 89.0f;
		if (Pitch < -89.0f)
			Pitch = -89.0f;
	}

	UpdateCameraVectors();
}

void Camera::ProcessMouseScroll(float yoffset) {
	if (Zoom >= 1.0f && Zoom <= 45.0f)
		Zoom -= yoffset;
	if (Zoom <= 1.0f)
		Zoom = 1.0f;
	if (Zoom >= 45.0f)
		Zoom = 45.0f;
}

void Camera::UpdateCameraVectors() {
	glm::vec3 front;
	front.x = cos(glm::radians(Yaw)) * cos(glm::radians(Pitch));
	front.y = sin(glm::radians(Pitch));
	front.z = sin(glm::radians(Yaw)) * cos(glm::radians(Pitch));
	Front = glm::normalize(front);

	Right = glm::normalize(glm::cross(Front, WorldUp));
	Up = glm::normalize(glm::cross(Right, Front));
}